One other data point in all this.

As we all probably know all too well, some drives/players read/play CD media better than others.

Case in point -- using Exact Audio Copy with heavily played commercially-manufactured older audio 
CD's. Visual inspection of the CD surface shows superficial scratching in the plastic but no deep 
gouges. This was confirmed under a magnifier lamp -- scuffs,scratches but no gouges or holes.

In a circa 2003 NEC DVD+RW drive, this disc could not be ingested by EAC. Error and timing rates 
made the final track unreadable. Yet, the disc could be copied using Roxio on a circa 2000 Plextor 
CDRW drive (same drive for read and write) and playback of the allegedly fatally-damaged track 
sounded just fine (no digital glitches or dropouts) in all players tested of the CDR media. However, 
playback of the original disc failed in some players. Applying EAC on a circa 2006 Plextor Pro 
DVD+/-RW drive netted a successful ingestion. EAC did report only 96% quality, which mean a good 
deal of error-correction was applied. However, examining the WAV file at the time-points that choked 
the NEC drive revealed nothing amiss in the waveform, and the audio sounded just fine, so that 
hearty error-correction apparently did its job and made the right "decisions".

I'd say this is all living precariously close to the edge of losing data, and the smart collector or 
archivist would probably ingest all his commercial CD's onto a managed hard drive system since so 
many titles are going out of print. Some people in some climates also have more trouble with "CD 
rot" type failures than others. I've only had two problem with commercially-manufactured CD's in my 
life and both times the problems were manufacturing errors and the record companies replaced the 
defective discs.

-- Tom Fine